Since 2011, Mr. Spitzer was paid at least $2 million by the cable network—including over $1 million after his short-lived venture into prime-time programming had already been canceled.

His well-compensated television work supplemented a healthy income that Mr. Spitzer receives from his family's portfolio of white-glove residential apartment buildings in New York City, which earned him and his wife over $2.5 million last year.

The details of Mr. Spitzer's previously opaque financial life—along with tidbits about his expenses for household help (modest) and income from academic work (not much)—were revealed in copies of his tax returns from the past two years, which Mr. Spitzer's campaign for city comptroller provided to The New York Times on Wednesday.

The disclosure came after weeks of pressure from Scott M. Stringer, another Democrat running for comptroller, who noted that just last year Mr. Spitzer had castigated Mitt Romney for not disclosing complete tax records in the presidential contest.

Mr. Spitzer's campaign invited a reporter to review the documents at the Fifth Avenue office of his family real estate empire, which is doubling as a cramped, five-aides-to-a-room campaign headquarters. The suite has amenities like Art Deco detailing and showstopping views of Central Park, another indication that Mr. Spitzer, who is self-financing his campaign, has a pecuniary edge over Mr. Stringer, the Manhattan borough president, who agreed to abide by the city's strict campaign spending limits.

The tax documents offer a glimpse into the financial life of a wealthy scion. Mr. Spitzer receives a $180,000 salary to help run his family business, and a majority of his annual income derives from real estate holdings.

Mr. Spitzer earned less than $10,000 from teaching at City University of New York in 2011, and less than $5,000 last year. Side work as a writer, a consultant and a speaker netted him about $50,000 in fees last year.

He and his wife, Silda Wall Spitzer, are living apart, but they filed a joint return for 2012. Ms. Wall Spitzer earned $125,325 last year at NewWorld Capital Group, a private equity firm. She earned about $250,000 in 2011 at her previous job at a hedge fund.

The couple donated $154,925 to charity last year, about 3.6 percent of their total income. Mr. Spitzer also oversees a charitable trust that donates on behalf of his parents, and Ms. Wall Spitzer has long been involved in a children's charity she founded. The couple spent about $60,000 annually on household employees.

Mr. Spitzer's affluence has allowed him to pay for early and frequent television advertising. While a reporter reviewed the documents, Mr. Spitzer was in his office next door, comparing two versions of a political advertisement on an Apple laptop.

He and his wife earned an adjusted gross income of $4.27 million last year.

Asked about the source of $147,834 from the sale of an unidentified property, Mr. Spitzer took a moment to ponder. He eventually clarified that the money represented his proceeds from a sale of a unit at 210 Central Park South, a 1966 apartment house built by his father.

A spokeswoman for Mr. Stringer, who released five years of complete tax returns, made clear the campaign was unimpressed by the release of the documents. "It's unfortunate that it took an entire month of public pressure to force Eliot to release two years of his tax returns, and notable that he still refuses to release the remaining three years," the spokeswoman, Audrey Gelman, said.

Mr. Stringer, who was running unopposed until last month, is intent on raising additional money to stave off the Spitzer juggernaut. He has raised $410,000 since Mr. Spitzer entered the race a month ago, and he held a fund-raiser on Tuesday that attracted a crowd of fashionable New Yorkers, including the television star Lena Dunham, who said she wanted "a candidate with a record of respecting women and the issues that matter to them."

Mr. Stringer appeared pleased. "No one ever thought that municipal finance could be sexy," he told the crowd.

—By Michael M. Grynbaum, The New York Times.

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